In the field of secondary battery, JP 2003-297412 A, for example, discloses a winding apparatus for fabricating an electrode assembly in which a positive electrode sheet and a negative electrode sheet are wound spirally with separators interposed therebetween. As disclosed in this publication, the winding apparatus winds the positive electrode sheet and the negative electrode sheet while correcting misalignment of the electrode sheets so that winding misalignment of the electrode sheets does not occur.